Trump lashes out at Russia probe as 'McCarthyism'

US President Donald Trump has stepped up his attacks on special counsel Robert Mueller's probe into Russian interference in the 2016 election, likening it to "McCarthyism"

US President Donald Trump on Sunday angrily denounced the federal probe of Russia's 2016 election meddling as "McCarthyism at its WORST!," insisting he had authorized his White House counsel to testify to bring the matter to a close.

Trump's Twitter storm was set off by a front-page report in the New York Times that said White House counsel Don McGahn had provided Special Counsel Robert Mueller with an unusually detailed account of Trump's thinking during key episodes under investigation.

Trump -- who had already addressed the issue late Saturday -- stepped up his attacks on the story and the probe in a series of angry morning tweets, slamming The New York Times for implying that McGahn had turned on him.

"I have nothing to hide ... and have demanded transparency so that this Rigged and Disgusting Witch Hunt can come to a close.

"So many lives have been ruined over nothing - McCarthyism at its WORST!"

Mueller is investigating whether the president sought to obstruct justice as well as whether his campaign colluded with Russia's covert effort to sway the 2016 presidential election in Trump's favor.

In more than 30 hours of testimony over the past nine months, the Times said McGahn laid out for investigators Trump's fury over the probe and the ways in which he asked McGahn to respond to it.

Among the episodes he testified to were Trump's firing of former FBI director James Comey, and his obsession with putting a loyalist in charge of the probe, according to the Times. It noted that McGahn played a key role in stopping Trump from firing Mueller, who was made special counsel after Comey's firing.

Trump called the story a "Fake piece" and seemed particularly incensed at the suggestion that McGahn was a "RAT" like John Dean, the former White House counsel who testified against president Richard Nixon during the Watergate scandal.

"The Failing New York Times wrote a story that made it seem like the White House Councel [sic] had TURNED on the President, when in fact it is just the opposite - & the two Fake reporters knew this. This is why the Fake News Media has become the Enemy of the People. So bad for America!"

"Study the late Joseph McCarthy, because we are now in period with Mueller and his gang that make Joseph McCarthy look like a baby! Rigged Witch Hunt!"